Irish American Joe Biden is the Democrat Donald Trump most fears running against according to key political analyst Mike Allen of  Axios.com.

Biden’s street cred with white working-class voters gives Trump nightmares as he feels no other Democratic candidate has anything like the rapport Biden has.

Biden, though a former senator from Delaware, was born in Scranton Pennsylvania where his dad was a car salesman. Pennsylvania is a must win for Trump and Biden would be a very tough opponent.

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Credit: RollingNews

Credit: RollingNews

Though Biden is 75, Trump will hardly be able to use the age issue against him as he himself is 72.

Biden has long experience working the white ethnic working class vote and will concede nothing to Trump.

Given that and the fact that Pennsylvania is the state he worries most about flipping against him Trump has reason to feel threatened.

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He knows that neither Bernie Sanders nor Elizabeth Warren has such credibility with those voters. Biden does.

The key constituency next time will be white working-class voters who went for Obama and then Trump. Will they swing back to the Democratic side? Biden certainly seems to think he can regain them.

Trump told CBS just after the Singapore summit: "I dream about Biden. That's a dream. ... I'd love to have it be Biden." What Trump meant was "wouldn't." https://t.co/fysrcjGI42

— Axios (@axios) July 25, 2018

Republican sources tell Allen “ Pennsylvania, where Trump campaigned frequently and fervently in 2016, will be the toughest to hold of all the battleground states that put him in office.

"There's a reason Pennsylvania had eluded Republican presidential candidates as long as it did," said GOP operative Josh Holmes, president of the Cavalry LLC issue management firm.

"You need a combination of a really effective campaign, a perfect message, and a good environment. Trump had it in 2016 but Biden could well spoil the party in 2020.

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Who is lurking in the shadows for Trump as he looks ahead to 2020? Ryan Johnson/Wikimedia Commons